My experience in large(r) projects with Nim is very positive. Two things I found particularly helpful are the module system and the "on the fly" documentation. As for compile time I've never had reason to complain but I'm not a speed fanatic; moreover Nim (modularity) allows for simple test builds using 'when isMainModule', so each developer can deliver his code in a state known to compile.
About the only thing to complain about is Nim's "weird" names in the resulting C code because that makes it harder to annotate it for statical analysis. But then it seems that @Araq has plans to build SA capabilities in Nim itself; I'm not sure how soon though.
